The mammalian testis is a tissue of highly-structured micro-environments, whose importance in the process of spermatogenesis is unknown, and all of which are destroyed by putting the cells into primary culture. While the microenvironment changes in culture are largely unknown, what is known is that few of the current methods of culturing cells from the mammalian testis produce mature germ cells, and none produce them in quantity or in consistently repeatable units (such as ?48 wells of spermatogenesis?). There is a large un-met need for such methods in at least two situations: 1) in pharmaceutical discovery and development, in the case where a lead compound produces testis damage and such a tool would be invaluable for screening possible backup compounds using less compound, and 2) in screening environmental compounds, where the number of chemicals with unknown biological activity is vastly larger than the resources to test them in animals. The methods developed to date can support germ cell viability and development only for a very short duration, and none can capture or support the last half of spermatogenesis, or combine spermatogenesis with steroidogenesis.

Tissue engineering offers another approach to this problem. The use of highly structured microenvironments such as those routinely considered and used by tissue engineers might do a better job of supporting spermatogenesis in culture. This workshop is intended to bring together experts in testis physiology and toxicology with tissue engineers to brainstorm ways of creating environments in vitro which might be more conducive to maintaining spermatogenesis. The workshop will feature active discussion sessions, and end with short presentations from funding agencies who might support this work. The goal is to finish our short workshop with ideas for 2-7 different models which could feasibly be tried in the near future.

PROGRAM: Wednesday, October 26

8:00-8:30 Breakfast

8:30-8:35Welcome and Introduction Thomas Hartung, Johns Hokins CAAT

8:35-8:40Introduction to HESI and the DART Committee James Kim, HESI

8:40-8:50Welcome—"Why We Are Here and What We Hope to Accomplish" Louise Saldutti, Merck